RGB curves - Why does adjusting the G curve also result in a change in R and B channels?

Software RawTherapee
23

I did something similar in non-luminosity blending mode, don’t compare the values with the previous post:

R: 27,1 -----> 63,9
G: 51,0 -----> 45,5
B: 85,1 -----> 78,4

Closer, but they do change.

EDIT: if you want to see the .pp3
20180811_Koblenz_516_Boppard_Innenstadt.DNG.pp3 (12,2 KB)

The raw file is found in this thread.